iPhone SDK reachabilityWithAddress问题

Question

我需要检查仅与IP地址的连接。我试图用Apple Reachability类来实现，使用reachabilityWithAddress选项。而我的问题是我可以在callAddress.sin_addr.s_addr字段中放置任何IP地址，并且statusText总是“可伸缩”。我该如何确切地检查IP地址的连接？

-(BOOL)reachabilityTest { 

struct sockaddr_in callAddress; 
callAddress.sin_len = sizeof(callAddress); 
callAddress.sin_family = AF_INET; 
callAddress.sin_port = htons(24); 
callAddress.sin_addr.s_addr = inet_addr("212.83.3.190"); 
Reachability *hostReach = [[Reachability reachabilityWithAddress:&callAddress] retain]; 

NetworkStatus netStatus = [hostReach currentReachabilityStatus]; 

if (netStatus == NotReachable) 
{ 
    NSLog(@"NotReachable"); 
    statusField.text = @"NOT reachable"; 
    return NO; 
} 

if (netStatus == ReachableViaWiFi) 
{ 
    NSLog(@"ReachableViaWiFi"); 
    statusField.text = @"reachable"; 
    return YES; 
} 
[Reachability release]; 
} 

Answer 1

而不是使用可达性类，走老派并打开它的TCP连接。如果对connect()的回复是EHOSTUNREACH，那么你不能。如果响应是ECONNREFUSED，或者连接成功，那么你可以。